pipe: kill ->map() and ->unmap()

all pipe_buffer_operations have the same instances of those...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

drivers/char/virtio_console.c

@@ -901,9 +901,9 @@ static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 		if (len + offset > PAGE_SIZE)
 			len = PAGE_SIZE - offset;
 
-		src = buf->ops->map(pipe, buf, 1);
+		src = kmap_atomic(buf->page);
 		memcpy(page_address(page) + offset, src + buf->offset, len);
-		buf->ops->unmap(pipe, buf, src);
+		kunmap_atomic(src);
 
 		sg_set_page(&(sgl->sg[sgl->n]), page, len, offset);
 	}

fs/fuse/dev.c

@@ -667,7 +667,7 @@ static void fuse_copy_finish(struct fuse_copy_state *cs)
 		struct pipe_buffer *buf = cs->currbuf;
 
 		if (!cs->write) {
-			buf->ops->unmap(cs->pipe, buf, cs->mapaddr);
+			kunmap_atomic(cs->mapaddr);
 		} else {
 			kunmap_atomic(cs->mapaddr);
 			buf->len = PAGE_SIZE - cs->len;
@@ -706,7 +706,7 @@ static int fuse_copy_fill(struct fuse_copy_state *cs)
 
 			BUG_ON(!cs->nr_segs);
 			cs->currbuf = buf;
-			cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
+			cs->mapaddr = kmap_atomic(buf->page);
 			cs->len = buf->len;
 			cs->buf = cs->mapaddr + buf->offset;
 			cs->pipebufs++;
@@ -874,7 +874,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
 out_fallback_unlock:
 	unlock_page(newpage);
 out_fallback:
-	cs->mapaddr = buf->ops->map(cs->pipe, buf, 1);
+	cs->mapaddr = kmap_atomic(buf->page);
 	cs->buf = cs->mapaddr + buf->offset;
 
 	err = lock_request(cs->fc, cs->req);

fs/pipe.c

@@ -225,52 +225,6 @@ static void anon_pipe_buf_release(struct pipe_inode_info *pipe,
 		page_cache_release(page);
 }
 
-/**
- * generic_pipe_buf_map - virtually map a pipe buffer
- * @pipe:	the pipe that the buffer belongs to
- * @buf:	the buffer that should be mapped
- * @atomic:	whether to use an atomic map
- *
- * Description:
- *	This function returns a kernel virtual address mapping for the
- *	pipe_buffer passed in @buf. If @atomic is set, an atomic map is provided
- *	and the caller has to be careful not to fault before calling
- *	the unmap function.
- *
- *	Note that this function calls kmap_atomic() if @atomic != 0.
- */
-void *generic_pipe_buf_map(struct pipe_inode_info *pipe,
-			   struct pipe_buffer *buf, int atomic)
-{
-	if (atomic) {
-		buf->flags |= PIPE_BUF_FLAG_ATOMIC;
-		return kmap_atomic(buf->page);
-	}
-
-	return kmap(buf->page);
-}
-EXPORT_SYMBOL(generic_pipe_buf_map);
-
-/**
- * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer
- * @pipe:	the pipe that the buffer belongs to
- * @buf:	the buffer that should be unmapped
- * @map_data:	the data that the mapping function returned
- *
- * Description:
- *	This function undoes the mapping that ->map() provided.
- */
-void generic_pipe_buf_unmap(struct pipe_inode_info *pipe,
-			    struct pipe_buffer *buf, void *map_data)
-{
-	if (buf->flags & PIPE_BUF_FLAG_ATOMIC) {
-		buf->flags &= ~PIPE_BUF_FLAG_ATOMIC;
-		kunmap_atomic(map_data);
-	} else
-		kunmap(buf->page);
-}
-EXPORT_SYMBOL(generic_pipe_buf_unmap);
-
 /**
  * generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer
  * @pipe:	the pipe that the buffer belongs to
@@ -351,8 +305,6 @@ EXPORT_SYMBOL(generic_pipe_buf_release);
 
 static const struct pipe_buf_operations anon_pipe_buf_ops = {
 	.can_merge = 1,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = anon_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -361,8 +313,6 @@ static const struct pipe_buf_operations anon_pipe_buf_ops = {
 
 static const struct pipe_buf_operations packet_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = anon_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -410,9 +360,15 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
 
 			atomic = !iov_fault_in_pages_write(iov, chars);
 redo:
-			addr = ops->map(pipe, buf, atomic);
+			if (atomic)
+				addr = kmap_atomic(buf->page);
+			else
+				addr = kmap(buf->page);
 			error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic);
-			ops->unmap(pipe, buf, addr);
+			if (atomic)
+				kunmap_atomic(addr);
+			else
+				kunmap(buf->page);
 			if (unlikely(error)) {
 				/*
 				 * Just retry with the slow path if we failed.
@@ -538,10 +494,16 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
 
 			iov_fault_in_pages_read(iov, chars);
 redo1:
-			addr = ops->map(pipe, buf, atomic);
+			if (atomic)
+				addr = kmap_atomic(buf->page);
+			else
+				addr = kmap(buf->page);
 			error = pipe_iov_copy_from_user(offset + addr, iov,
 							chars, atomic);
-			ops->unmap(pipe, buf, addr);
+			if (atomic)
+				kunmap_atomic(addr);
+			else
+				kunmap(buf->page);
 			ret = error;
 			do_wakeup = 1;
 			if (error) {

fs/splice.c

@@ -136,8 +136,6 @@ static int page_cache_pipe_buf_confirm(struct pipe_inode_info *pipe,
 
 const struct pipe_buf_operations page_cache_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = page_cache_pipe_buf_confirm,
 	.release = page_cache_pipe_buf_release,
 	.steal = page_cache_pipe_buf_steal,
@@ -156,8 +154,6 @@ static int user_page_pipe_buf_steal(struct pipe_inode_info *pipe,
 
 static const struct pipe_buf_operations user_page_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = page_cache_pipe_buf_release,
 	.steal = user_page_pipe_buf_steal,
@@ -547,8 +543,6 @@ EXPORT_SYMBOL(generic_file_splice_read);
 
 static const struct pipe_buf_operations default_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = generic_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,
@@ -564,8 +558,6 @@ static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe,
 /* Pipe buffer operations for a socket and similar. */
 const struct pipe_buf_operations nosteal_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = generic_pipe_buf_release,
 	.steal = generic_pipe_buf_nosteal,
@@ -767,13 +759,13 @@ int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 		goto out;
 
 	if (buf->page != page) {
-		char *src = buf->ops->map(pipe, buf, 1);
+		char *src = kmap_atomic(buf->page);
 		char *dst = kmap_atomic(page);
 
 		memcpy(dst + offset, src + buf->offset, this_len);
 		flush_dcache_page(page);
 		kunmap_atomic(dst);
-		buf->ops->unmap(pipe, buf, src);
+		kunmap_atomic(src);
 	}
 	ret = pagecache_write_end(file, mapping, sd->pos, this_len, this_len,
 				page, fsdata);
@@ -1067,9 +1059,9 @@ static int write_pipe_buf(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 	void *data;
 	loff_t tmp = sd->pos;
 
-	data = buf->ops->map(pipe, buf, 0);
+	data = kmap(buf->page);
 	ret = __kernel_write(sd->u.file, data + buf->offset, sd->len, &tmp);
-	buf->ops->unmap(pipe, buf, data);
+	kunmap(buf->page);
 
 	return ret;
 }
@@ -1536,10 +1528,10 @@ static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 	 * pages and doing an atomic copy
 	 */
 	if (!fault_in_pages_writeable(sd->u.userptr, sd->len)) {
-		src = buf->ops->map(pipe, buf, 1);
+		src = kmap_atomic(buf->page);
 		ret = __copy_to_user_inatomic(sd->u.userptr, src + buf->offset,
 							sd->len);
-		buf->ops->unmap(pipe, buf, src);
+		kunmap_atomic(src);
 		if (!ret) {
 			ret = sd->len;
 			goto out;
@@ -1549,13 +1541,13 @@ static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 	/*
 	 * No dice, use slow non-atomic map and copy
  	 */
-	src = buf->ops->map(pipe, buf, 0);
+	src = kmap(buf->page);
 
 	ret = sd->len;
 	if (copy_to_user(sd->u.userptr, src + buf->offset, sd->len))
 		ret = -EFAULT;
 
-	buf->ops->unmap(pipe, buf, src);
+	kunmap(buf->page);
 out:
 	if (ret > 0)
 		sd->u.userptr += ret;

include/linux/pipe_fs_i.h

@@ -82,23 +82,6 @@ struct pipe_buf_operations {
 	 */
 	int can_merge;
 
-	/*
-	 * ->map() returns a virtual address mapping of the pipe buffer.
-	 * The last integer flag reflects whether this should be an atomic
-	 * mapping or not. The atomic map is faster, however you can't take
-	 * page faults before calling ->unmap() again. So if you need to eg
-	 * access user data through copy_to/from_user(), then you must get
-	 * a non-atomic map. ->map() uses the kmap_atomic slot for
-	 * atomic maps, you have to be careful if mapping another page as
-	 * source or destination for a copy.
-	 */
-	void * (*map)(struct pipe_inode_info *, struct pipe_buffer *, int);
-
-	/*
-	 * Undoes ->map(), finishes the virtual mapping of the pipe buffer.
-	 */
-	void (*unmap)(struct pipe_inode_info *, struct pipe_buffer *, void *);
-
 	/*
 	 * ->confirm() verifies that the data in the pipe buffer is there
 	 * and that the contents are good. If the pages in the pipe belong
@@ -150,8 +133,6 @@ struct pipe_inode_info *alloc_pipe_info(void);
 void free_pipe_info(struct pipe_inode_info *);
 
 /* Generic pipe buffer ops functions */
-void *generic_pipe_buf_map(struct pipe_inode_info *, struct pipe_buffer *, int);
-void generic_pipe_buf_unmap(struct pipe_inode_info *, struct pipe_buffer *, void *);
 void generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *);
 int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *);
 int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *);

kernel/relay.c

@@ -1195,8 +1195,6 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe,
 
 static const struct pipe_buf_operations relay_pipe_buf_ops = {
 	.can_merge = 0,
-	.map = generic_pipe_buf_map,
-	.unmap = generic_pipe_buf_unmap,
 	.confirm = generic_pipe_buf_confirm,
 	.release = relay_pipe_buf_release,
 	.steal = generic_pipe_buf_steal,

kernel/trace/trace.c

@@ -4316,8 +4316,6 @@ static void tracing_spd_release_pipe(struct splice_pipe_desc *spd,
 
 static const struct pipe_buf_operations tracing_pipe_buf_ops = {
 	.can_merge		= 0,
-	.map			= generic_pipe_buf_map,
-	.unmap			= generic_pipe_buf_unmap,
 	.confirm		= generic_pipe_buf_confirm,
 	.release		= generic_pipe_buf_release,
 	.steal			= generic_pipe_buf_steal,
@@ -5194,8 +5192,6 @@ static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
 /* Pipe buffer operations for a buffer. */
 static const struct pipe_buf_operations buffer_pipe_buf_ops = {
 	.can_merge		= 0,
-	.map			= generic_pipe_buf_map,
-	.unmap			= generic_pipe_buf_unmap,
 	.confirm		= generic_pipe_buf_confirm,
 	.release		= buffer_pipe_buf_release,
 	.steal			= generic_pipe_buf_steal,